Percent increase, percent decrease and percent error

Answer Key - Grade 7 Math Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   Row 100 | 60; row 10 | 6; then a blank row for the new amount. Ari's cookie recipe uses 60 grams of flour. Ari makes a bigger batch with 30% more flour. How many grams of flour does the bigger batch use?

   78
2. 2.

   Row 100 | 80; row 10 | 8; then a blank row for the new amount. Jun's water bottle holds 80 ounces. Jun drinks 20% of the water before the bus. How many ounces are left?

   64
3. 3.

   Row 100 | 50; row 10 | 5; then a blank row for the new amount. Kira's sticker sheet has 50 stickers. Kira gives away 30% of them at lunch. How many stickers are left?

   35
4. 4.

   Milo counts 90 people at the park last Saturday. This Saturday there are 10% more people, and the swing line is long. How many people are at the park?

   99
5. 5.

   Noah's bamboo shoot is 70 centimeters tall. A week later it is 50% taller. How tall is the shoot now?

   105
6. 6.

   A bike trail near Pia's town is 64 miles long. The town makes it 25% longer. How long is the new trail?

   80
7. 7.

   Ren's class had 150 pencils. 20% of the pencils got lost in the great desk cleanup. How many pencils are left?

   120
8. 8.

   Tala's video is 60 minutes long. Tala cuts it by 25% to fit the school show. How many minutes long is the new video?

   45
9. 9.

   Ari's town grew by 5% this year. By what number do you multiply last year's population to get this year's population?

   1.05
10. 10.

    Jun's watering can leaks, so it holds 25% less water than before. By what number do you multiply the old amount of water to get the new amount?

    0.75